Cycling, also called bicycling or biking, is the use of bicycles for transport, recreation, or for sport. Persons engaged in cycling are referred to as “cyclists“,”bikers“, or less commonly, as “
bicyclists“. Apart from two-wheeled bicycles, “cycling” also includes the riding of unicycles, tricycles, quadracycles, and similar human-powered vehicles (HPVs).Cycling is widely regarded as a very effective and efficient mode of transportation optimal for short to moderate distances. Bicycles provide numerous benefits by comparison with motor vehicles, including the sustained physical exercise necessarily involved in cycling, that cycling involves a reduced consumption of fossil fuels, less air or noise pollution, much reduced traffic congestion, easier parking, greater maneuverability, and access to both roads and paths. The advantages also include reduced financial cost to the user as well as to society at large (negligible damage to roads, less road area required). Among the disadvantages of cycling are the inherent instability of the bicycle, the immensely reduced protection in crashes (especially in collisions with motor vehicles), longer travel time (except in densely populated areas), vulnerability to weather conditions, difficulty in transporting passengers, competition (and interference) with socially beneficial forms of mass public transit, a persistent tendency for cyclists to intrude into pedestrian areas, and the particular levels of skill and fitness required by cycling.
In many countries, the most commonly used vehicle for road transport is a utility bicycle. These have frames with relaxed geometry, protecting the rider from shocks of the road and easing steering at low speeds.
Road bikes tend to have a more upright shape and a shorter wheelbase, which make the bike more mobile but harder to ride slowly. The design, coupled with low or dropped handlebars, requires the rider to bend forward more, utilizing stronger muscles (particularly the gluteus maximus) and reducing air resistance at high speed.
The price of a new bicycle can range from US$50 to more than US$20,000 (the highest priced bike in the world is the custom Madone by Damien Hirst, sold at $500,000 USD), depending on quality, type and weight (the most exotic road bicycles can weigh as little as 3.2 kg (7 lb)). However, UCI regulations stipulates a legal race bike cannot weigh less than 6.8 kg (14.99 lbs). Being measured for a bike and taking it for a test ride are recommended before buying.
The drivetrain components of the bike should also be considered. A middle grade dérailleur is sufficient for a beginner, although many utility bikes come equipped with hub gears. If the rider plans a significant amount of hillclimbing, a triple-crank (three chainrings) front gear system may be preferred. Otherwise, the relatively lighter and less expensive two chainrings may be better. Much simpler fixed wheel bikes are also available, and may be more suitable for commuters.
Many road bikes along with mountain bikes include clipless pedals to which special shoes attach, via a cleat, permitting the rider to pull on the pedals as well as push. Other possible accessories for the bicycle include front and back lights, bells or horns, disc brakes, child carrying seats, cycling computers with GPS, locks, bar tape, fenders (mud-guards), baggage racks, baggage carriers and pannier bags, water bottles and bottle cages.
For basic maintenance and repairs, cyclists can choose to carry a pump (or a CO2 cartridge), a puncture repair kit, a spare inner tube, and tire levers. Cycling can be more efficient and comfortable with special shoes, gloves, and shorts. In wet weather, riding can be more tolerable with waterproof clothes, such as cape, jacket, trousers (pants) and overshoes.
Items legally required in some jurisdictions, or voluntarily adopted for safety reasons, include bicycle helmets, generator or battery operated lights, reflectors, and audible signalling devices such as a bell or horn. Extras include studded tires and a bicycle computer.
Bikes can also be heavily customized, with different seat designs and handle bars, for example.